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Article
Publication date: 4 October 2019

Xiaoming Zhang, Chen Lei, Jun Liu, Jie Li, Jie Tan, Chen Lu, Zheng-Zheng Chao and Yu-Zhang Wan

In spite of the vehicle, magnetic field interference can be reduced by some measures and techniques in ammunition design and manufacturing stage, the corruption of the…

Abstract

Purpose

In spite of the vehicle, magnetic field interference can be reduced by some measures and techniques in ammunition design and manufacturing stage, the corruption of the vehicle magnetic field can still reach hundreds to thousands of nanoteslas. Besides, the magnetic field that the ferromagnetic materials generate in response to the strong magnetic field in the vicinity of the body. So, a real-time and accurate vehicle magnetic field calibration method is needed to improve the real-time measurement accuracy of the geomagnetic field for spinning projectiles.

Design/methodology/approach

Unlike the past two-step calibration method, the algorithm uses a linear model to calibrate the magnetic measurement error in real-time. In the method, the elliptical model of magnetometer measurement is established to convert the coefficients of hard and soft iron errors into the parameters of the elliptic equation. Then, the parameters are estimated by recursive least square estimator in real-time. Finally, the initial conditions for the estimator are established using prior knowledge method or static calibration method.

Findings

Studies show the proposed algorithm has remarkable estimation accuracy and robustness and it realizes calibration the magnetic measurement error in real-time. A turntable experiments indicate that the post-calibration residuals approximate the measurement noise of the magnetometer and the roll accuracy is better than 1°. The algorithm is restricted to biaxial magnetometers’ calibration in real-time as expressed in this paper. It, however, should be possible to broaden this method’s applicability to triaxial magnetometers' calibration in real-time.

Originality/value

Unlike the past two-step calibration method, the algorithm uses a linear model to calibrate the magnetic measurement error in real-time and the calculation is small. Besides, it does not take up storage space. The proposed algorithm has remarkable estimation accuracy and robustness and it realizes calibration the magnetic measurement error in real time. The algorithm is restricted to biaxial magnetometers’ calibration in real-time as expressed in this paper. It, however, should be possible to broaden this method’s applicability to triaxial magnetometers’ calibration in real-time.

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Article
Publication date: 10 May 2019

Xiao-Shun Zhao, Li Yu, Xue Yang and Si-Yu Zhang

The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution.

Abstract

Purpose

The purpose of this study was to develop a new folding method for modeling complicated folded fabric with surfaces of revolution.

Design/methodology/approach

Irregular wrinkles and mesh distortions easily appear in the fold modeling of a complex curved surface. Aimed at this key technical problem, the segmentation mapping folding method (SMFM) is proposed in this paper. First, high-precision flattened planes were obtained by using segmentation mapping techniques. Second, the segmented planes were transformed into a folded and continuous geometric model by using matrix transformations. Finally, initial stress was used to modify the geometric folding errors, which ensured agreement with the inflated flexible fabric’s geometry and the original design.

Findings

Compared with the traditional folding method, SMFM has the advantages of good finite-element mesh quality, large radial compression rate, regular folds, etc. The surface area error and the volume error of the inflated single torus established by SMFM were only 1.2 per cent, showing that SMFM has high modeling accuracy. The numerical results of an inflatable re-entry vehicle are presented to demonstrate the reliability, feasibility and applicability of SMFM. Moreover, the stress modification reduced the problems of stress concentration and mesh distortions, improving the accuracy and stability of the numerical calculations.

Originality/value

In this paper, for the first time, a folding method for modeling complicated folded fabric is proposed. This methodology can be used to model the multidimensional compression and regular folds of complex surfaces of revolution that cannot be flattened and to improve the accuracy and stability of the numerical calculations.

Details

Engineering Computations, vol. 36 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

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Book part
Publication date: 25 September 2020

Yan Zhu

Friendships, an important form of people’s everyday relationships with others, have been studied by many scholars from different disciplines. However, there is limited…

Abstract

Friendships, an important form of people’s everyday relationships with others, have been studied by many scholars from different disciplines. However, there is limited research on friendship in the context of childhood, particularly that of Chinese rural children. This chapter presents findings from an in-depth study on Chinese children’s understandings and experiences of friendships with peers in the context of a rural primary boarding school. Data for this research were collected through an intensive five-month study, using an ethnographic approach, in a rural primary boarding school (given the pseudonym ‘Central Primary School’) in the western area of China in 2016. This chapter discusses parents’ influences on children’s selection of friends, particularly their ‘good’ friends, and their understandings of the functions of making friends in the context of rural China. It unpacks parents’ interventions on children’s friendships by discussing the moralised hierarchical relationship between children and their parents – children are expected to show obedience to parents. Then, it argues that the Confucian-collectivist values construct a relationship between a child’s individual achievement and their family’s collective good, which makes friendship not only an individual issue but also a collective one too.

Details

Bringing Children Back into the Family: Relationality, Connectedness and Home
Type: Book
ISBN: 978-1-83867-197-6

Keywords

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Article
Publication date: 14 June 2021

Syed Abdul Rehman Khan, Zhang Yu, Muhammad Umar, Ana Beatriz Lopes de Sousa Jabbour and Rahul S. Mor

This study aims to examine the impact of Covid-19 on social and eco-environmental sustainability. It will also investigate the effect of advanced technologies in the…

Abstract

Purpose

This study aims to examine the impact of Covid-19 on social and eco-environmental sustainability. It will also investigate the effect of advanced technologies in the post-pandemic era.

Design/methodology/approach

To get the robust findings, GMM (Generalized Method of Moments) modeling is employed on the panel data of 50 countries across the globe.

Findings

The outcomes indicate that gross fixed capital, logistical operations, knowledge spillover are positive, while Covid-19 is negatively associated with international trade. The results also revealed that Covid-19 spurs poverty and vulnerable employment, while the fertility rate increase creates pressure on economic growth. Also, fossil fuel and energy consumption contribute to carbon emission, while green and advanced technologies may mitigate the environment's adverse effects.

Originality/value

This study is the first of its kind to provide a solution to the challenges posed by the Covid-19 pandemic in the post-pandemic environment. Furthermore, researchers, managers and legislators can use this article's findings to formulate relevant policies for post-pandemic.

Details

Journal of Enterprise Information Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1741-0398

Keywords

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